# GDM Configuration Customization file.
#
# This file is the appropriate place for specifying your customizations to the
# GDM configuration. If you run gdmsetup, it will automatically edit this
# file for you and will cause the daemon and any running GDM GUI programs to
# automatically update with the new configuration. Not all configuration
# options are supported by gdmsetup, so to modify some values it may be
# necessary to modify this file directly by hand.
#
# To hand-edit this file, simply add or modify the key=value combination in
# the appropriate section in the template below. Refer to the comments in the
# gdm.conf file for information about each option. Also refer to the reference
# documentation.
#
# If you hand edit a GDM configuration file, you should run the following
# command to get the GDM daemon to notice the change. Any running GDM GUI
# programs will also be notified to update with the new configuration.
#
# gdmflexiserver --command="UPDATE_CONFIG <configuration key>"
#
# For example, the "Enable" key in the "[debug]" section would be specified by
# "debug/Enable".
#
# You can also run gdm-restart or gdm-safe-restart to cause GDM to restart and
# re-read the new configuration settings. You can also restart GDM by sending
# a HUP or USR1 signal to the daemon. HUP behaves like gdm-restart and causes
# any user session started by GDM to exit immediately while USR1 behaves like
# gdm-safe-restart and will wait until all users log out before restarting GDM.
#
# For full reference documentation see the gnome help browser under
# GNOME|System category. You can also find the docs in HTML form on
# http://www.gnome.org/projects/gdm/
#
# NOTE: Lines that begin with "#" are considered comments.
#
# Have fun!
[daemon]
[security]
[xdmcp]
[gui]
[greeter]
[chooser]
[debug]
[servers]# Override display 1 to use Xgl
0=Xgl
[server-Xgl]
name=Xgl server
command=/usr/bin/Xgl :0 -fullscreen -ac -accel glx:pbuffer -accel xv:fbo
flexible=true

This will make it so your grub console will require a password to edit the lines, and the recovery modes won't work unless the password is typed. To access the other grub options at the menu, follow the instructions at the bottom of the screen. It will be something like pressing p and typing your password.

How to disable history listing in Console mode

export HISTFILESIZE=4
unset HISTFILE=5
# Change this to a reasonable number of lines to save, I like to save only 100.
export HISTSIZE=1
# Ignores duplicate lines next to each other
export HISTCONTROL=ignoredups

This will disable Bash history for the user, retaining keystroke history and recall to use while limiting recall history to 100 lines. This will also not record duplicate lines next to each other.

What: Quote from Wikipedia: "LoJack is an aftermarket vehicle tracking system that allows cars to be tracked by police after being stolen. The manufacturer claims a 90% recovery rate. The name "LoJack" is a play on the word "hijack," meaning the theft of a vehicle through force."

Why: If your laptop is ever stolen and connected to the Internet. You will be able to find out from what IP it connects to the Internet from and contact the authorities.

How:

Get a free dynamic IP account from one of the many providers. Here we will use DynDNS.

How to apt-get the easy way (Synaptic)

In the Installation Media tab, click Add. There are three separate repositories; Dapper Drake, Security Updates and Updates. Select each repository and check Officially supported, Restricted copyright, Community maintained (Universe) and Non-free (Multiverse). Ensure you click OK between each repository to save your changes

You should now see those three repositories under Channels. Make sure Officially supported, Restricted copyright, Community maintained (Universe) and Non-free (Multiverse) appears under each repository

To add backports and PLF (new versions of many applications. Unsupported. May contain illegal packages. Use at own risk.)

Settings -> Repositories

Click on Add and then Custom

Paste the following four lines into the box and click Add Repository, one line at a time:

Now you can type extended characters using the RightWin key (next to AltGr), according to this keyboard settings file.
Specifically, the lines that start with GDK_Multi_key are those that we can use here. The Compose key is actually GDK_Multi_key.